Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Gain access to PCB (use Insulation Mat as required)
Disconnect connector X1 from the PCB
Disconnect connector X1 from the PCB
Measurement:
Test 1:
Measure the resistance between the blue and white wires at the disconnected plug.
Resistance should be approximately 3.8kOhms.
Test 2:
Measure the resistance between the white wire at the disconnected plug to a suitable earth point.
Resistance should be greater than 1M Ohm.
Measure the resistance between the blue and white wires at the disconnected plug.
Resistance should be approximately 3.8kOhms.
Test 2:
Measure the resistance between the white wire at the disconnected plug to a suitable earth point.
Resistance should be greater than 1M Ohm.
Isolate as per TOPs P4
and refit as necessary